Rectum lining thickening/tumour

I have been experiencing bowel changes from past 4 month, GP did stool test to check for inflammation and other infections and put me on 3 weeks antibiotics for Hpylori. Last month I did CT abdomen and it was found my rectum wall thickened with 14mm and awaiting colonoscopy. Sometimes I get mucus/blood in my stools. I'm scared of worst things. Does anyone experienced like this.